From Black/White to Ultra Sun/Ultra Moon, Dark Pulse's TM was changed in favor of Frost Breath, a Special Ice-Type move that is guaranteed to land critical hits.
In Sword/Shield, TM79 was Retaliate, a Physical Normal-Type move that deals double damage if a teammate fainted on the previous turn.
Dark Pulse returned to being TM79 in Brilliant Diamond/Shining Pearl, but in Scarlet/Violet, Dazzling Gleam replaced it once again, a Special Fairy-Type move that hits all adjacent opponents in double battles.
It might also be worth mentioning that Frost Breath also replaced Dark Pulse in every Pokémon Mystery Dungeon game since Gates to Infinity
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